Effects of skeletonization on intraoperative flow and anastomosis diameter of internal thoracic arteries in coronary artery bypass grafting

Background. We examined the hypothesis that complete skeletonization of an internal thoracic artery (ITA) results in increased diameter of the graft for anastomosis and therefore improves graft flow in coronary artery bypass grafting. Methods. We studied 65 consecutive patients who underwent coronary artery bypass grafting, in which the left ITA was anastomosed to the left anterior descending artery. The first 20 consecutive ITA were harvested as a pedicle (group P) and later 45 consecutive ITAs were harvested as an ultrasonically skeletonized graft (group S). Intraoperative ITA graft mean flows were obtained with a transit-time flowmeter. Three diameters of the ITA graft were measured quantitatively in postoperative angiograms performed 14 ± 5 days after the coronary artery bypass grafting; D1, at the origin from the subclavian artery; D2, at the level of the second intercostal space; and D3, just proximal to the anastomosis. Results. Intraoperative mean flow was significantly greater in group S than in group P (S: 42.6 ± 29.1 mL/min versus P: 26.4 ± 16.1 mL/min, p = 0.03). Although the diameters D1 and D2 were not significantly different between groups, D3 was significantly larger in group S than in group p (S: 1.77 ± 0.28 mm versus P: 1.57 ± 0.17 mm, p = 0.02). Conclusions. Compared with pedicle harvesting, complete skeletonization of ITA may make it possible to anastomose an ITA with a larger diameter in coronary artery bypass grafting, which leads to increased graft flow by decreasing vascular resistance.